Guitar

ABSTRACT

An improved construction for a guitar in which an elongated sound bar made of aluminum, copper, or silver is passed between a lining strip at the side board of the guitar and a part fixed to the top board directly beneath the high-pitch-tuned end of the bridge with the intermediate portion of the sound bar spaced from the top board, thereby making it possible for a comparatively low-priced, medium or low-grade guitar to produce the excellent sound, volume and balanced tones and sounds between strings comparable to those of an expensive high-grade guitar.

United States Patent Imai at al.

1 1 Sept. 12,1972

[54] GUITAR 1,116,754 11/1914 Storle ..84/276 UX [72] Inventors: Mm lmai 224, awhome, 1,890,861 12/1932 Overton ..84/267 nlgashmakanm T FOREIGN PATENTS OR APPLICATIONS 10, 4-chome, l-ligashmakano, both f Nakanok Tokyo, Japan 573,322 10/1334 France]; 24/276 17, 1112 Gt'tain ..424 22 Filed: Dec. 1, 1970 tea I 9 21 APPL 93,943 Primary Examiner-Richard B. Wilkinson 1 Assistant Examiner-John F. Gonzales Attoqney-Beveridge & De Grandi [30] Foreign Application Priority Data Dec. 10, 1969 Japan ..44/99287 [57] ABSTRACT An improved construction for a guitar in which an [52] US. Cl ..84/267, 84/294 elongated sound bar made of aluminum. c pp or [51] Int. Cl. ..G10d l/08, GlOd 3/02 Silver is pa between a lining strip at the side board [58] Field of Search ..84/267, 268, 276, 291, 292, of the guitar and a P fixed t0 the p board irectly 34 294 274 275 beneath the high-pitch-tuned end of the bridge with the intermediate portion of the sound bar spaced from [5 References Cited the top board, thereby making it possible for a comparatively low-priced, medium or low-grade guitar to UNITED STATES PATENTS produce the excellent sound, volume and balanced tones and sounds between stn'ngs comparable to those 547,150 10/1895 Monson ..84/292 594,436 11/1897 Simpson ..84/268 expenswe mgh grade 651,146 6/1900 Rogers ..84/267 4 Claims, 9 Drawing Figures f 13 I6 I t" 1'; F 1 l 11 I 5 I H n i A L I H I v I I 5 2" 2 2 y A primary object of the present invention is to make I it possible for a low-priced, medium or lesser grade guitar to produce a good sound and tone well comparable to those of an expensive high-grade guitar by providing simple improvements to the former.

- It is another objectof the present invention to provide a high tone quality guitar withoutcausing any significantly increasingmanufacturing costs by making simple improvements in an inexpensive guitar.

Thisinvention, has been achieved as a result of a great number of experiments and repeated trials and errors, with help of intuition, chance and luck.

The principalconstituent of this invention is a sound bar comprising an elongated member made of Al, Cu or Ag. This sound bar is passed between the lining strip at the side of the guitar and a part fixed to the top board directly beneath the high-pitched tuned end of the bridge with the intermediate portion of said bar suitably spaced below the top board. It has been experimentally confirmed that this arrangement is helpful to increase the volume of sound, particularly of high-pitch tuned strings, resulting in good sound balance between strings and also improved tone.

The objects and advantages of the invention will be more fully understood from the following description of the embodiments thereto shown by way of example in the accompanying drawings in which:

FIG. 1 is a partially cut-away plan view of a guitar constructed according to the present invention;

FIG. 2 is a rear view of the guitar, with the back board being removed;

FIG. 3 is an enlarged cross-sectional view taken on the line lII-lll of FIG. 2;

FIG. 4 is a rear view of another embodiment of the present invention shown with the back board removed;

FIG. 5 is an enlarged cross-sectional view taken on the line V-V of FIG. 4; and

FIG. 6a to 6d are perspective views showing different forms of the sound bar.

Referring first to FIGS. 1 to 3, there is shown an embodiment of the present invention, wherein reference numeral 11 designates a neck, 12 a finger board, 13 a top board, 14 a sound hole, 15 a bridge, 16 a side board, 17 a lining strip attached at the juncture between the top board 13 and the side board 16, 18, pencil ribs or reinforcements, and playing strings 19 of which the three on the left side in FIG. 1 are those tuned to low pitch and the remaining three on the right side tuned to high pitch. All of the above-said elements may be found in conventional guitars.

Denoted by reference numeral 20 is a sound bar which constitutes the main feature of the present invention. This sound bar is an elongated round rod made of metal such as Al, Cu or Ag. As seen in FIG. 3, one end of said bar is fixedly inserted into a small block 21 glued to that part on the underside of the top board 13 which is just beneath the end 151 on the high-pitch tuned side of the bridge 15, while the other end 202 of said bar is fixedly inserted into a small block 22 glued to the inner face of the lining strip 17. As will also be seen, the portion of the sound bar 20 intermediate its ends 201 and 202 is suitably spaced from the underside of the top board 13. The end 202 may be directly inserted into the lining strip 17.

In FIGS. 4 and 5 is shown another embodiment where a bridge reinforcing rib, designated by reference numeral 23, is provided. Said rib 23 is fastened, by gluing or other means, to that part on the underside of the top board 13 which is directly beneath the bridge 15. In

this instance, one end 201 of the sound bar 20 may be directly inserted into the end 231 on the high-pitch side of the bridge reinforcing rib 23, as shown in FIG. 5. In order to facilitate such insertion, the end 201 of the sound bar 20 is preferably slightly bent up and also suitably pointed at its tip.

It is believed the information given below will prove helpful in practicing the present invention. In some types of guitar, an additional sound bar 20a, completely identical with the aforementioned sound bar 20, may be provichad on the low-pitch side as indicated by a phantom line in FIG. 2 in the same manner described above in connection with sound bar 20.

Generally, a somewhat high-priced medium-grade guitar has comparatively a good balance of sounds between strings. In such a guitar, provision of two sound bars, on both high-pitch and low-pitch sides, is effective for increasing the sound volume and improving the tone.

The configuration of the sound bar 20 is not restricted to being round or rod-shaped as in the above described embodiments; it may be of a spiralled tubular configuration as shown in FIG. 6a, or a cylindrical tubular configuration as shown in FIG. 6b, or one which is triangular in section as shown in FIG. 60, or channelshaped as shown in FIG. 6d. Test results however have shown that the spiralled tubular configuration is most preferred.

The material best suited for making the sound bar 20 is A, Cu and Ag. Au may be too expensive to meet certain objectives of the present invention.

The location of the sound bar 20 should preferably be within the range defined by line L, (see FIG. 1) which passes the upper edge (as viewed in FIG. 1) of the bridge 15 and a line L, which passes the lower edge of the high-pitch-side end 151 of the bridge 15 and which is inclined at an angle of 30 relative to the line L1.

. As described above, attachment of the sound bar or bars of the present invention at a prescribed location increases the volume of sound, particularly of the highpitch strings in a medium or lesser grade guitar which are usually lacking in such sound volume, and also improves the balancing of sounds as a whole as well as tone quality. To state it in a more specific way, initiation of the sound as produced by flipping of the strings, is improved, and also the sound is made clearer and is attenuated in a most natural manner. Further, the harmonics sounds with clear and crystal tones, and particularly, there is avoided sound like bongos, or tub" tones, by the low-pitch strings, which otherwise tends to be produced in a guitar where plywood is used for the top board. In summary, the resulting sound is full, well-balanced and well-toned, comparable to that of a high-grade guitar.

The reasons which are responsible for such effects are not yet theoretically determined. As stated before, the above results have been confirmed by a great number of experiments.

For determination of the volume of the sound, although it may be qualitatively measured by using electrical instruments, we used a 30 inclination test method which is commonly employed among guitar manufactures as a most expedient means. According to this method, a guitar to be tested is supported in an inclined position such that the top board will be inclined at an angle of 30 with respect to the horizontal plane. Then small, lightweight grains, such as sawdust, are uniformly scattered over the surface of the top board, and the movement of these small grains caused by flipping of the strings is observed. Such movement was observed as brisk in a guitar in which the sound bar of the present invention was incorporated. This is due to large amplitude of vibrations produced in the top board and the consequent large volume of sound.

To determine tone quality, although there is available, a method in which the wave forms of sounds are examined by use of an oscilloscope, it is extremely difficult to measure such tone quality quantitatively and objectively. Human ears are, after all, the most reliable measure. Applicants asked many professional guitar players and manufacturers to listen to the sound produced by the guitar constructed in accordance with the present invention. They all admitted splendidness of tone quality of our guitar.

While preferred embodiments of the invention have been illustrated by way of example in the drawings and particularly described above, it will be understood that modifications may be made in the construction and that the invention is in no way limited to the embodiments shown.-

What is claimed is:

1. In a guitar having a top board (13) a bridge (15) fixed to the top board intermediate the ends of the top board and extending transversely of the top board, a side board (16) extending along and defining the side of the guitar, and a lining strip (17) fixed at the juncture between the top board and the side board; the improvement comprising an elongated sound bar fixed in the guitar spaced below the top board with one end of the sound bar positioned directly beneath one end of said bridge and the other end fixed to said lining strip.

2. The guitar defined in claim 1 wherein said sound bar is made from a metallic material and is positioned within an angle on the rearward side of the bridge of approximately 30 made by the bridge and a line intersecting said one end of the bridge at approximately 30.

3. The guitar defined in claim 2 wherein said sound bar is made from a metal in a group consisting of Al, Cu and Ag.

4. The guitar defined in claim 3 further including a block fixed to the underside of said top piece directly beneath said one end of said bridge and wherein said one end of said sound bar is fixed to said block. 

1. In a guitar having a top board (13) a bridge (15) fixed to the top board intermediate the ends of the top board and extending transversely of the top board, a side board (16) extending along and defining the side of the guitar, and a lining strip (17) fixed at the juncture between the top board and the side board; the improvement comprising an elongated sound bar fixed in the guitar spaced below the top board with one end of the sound bar positioned directly beneath one end of said bridge and the other end fixed to said lining strip.
 2. The guitar defined in claim 1 wherein said sound bar is made from a metallic material and is positioned within an angle on the rearward side of the bridge of approximately 30* made by the bridge and a line intersecting said one end of the bridge at approximately 30* .
 3. The guitar defined in claim 2 wherein said sound bar is made from a metal in a group consisting of Al, Cu and Ag.
 4. The guitar defined in claim 3 further including a block fixed to the underside of said top piece directly beneath said one end of said bridge and wherein said one end of said sound bar is fixed to said block. 